DECNET-Plus and cluster sharing sysuaf etc.

[Allan Poulsen]

Hi Folks,

I have a configuration problem I am having a hard time to fix.
Situation is as follows:
I have two Alpha OpenVMS 7.3-2 nodes joined in a cluster. They share AT LEAST one disk (not the system disk). In order to enhance security we have placed SYSUAF.dat, Rightslist.dat and NetProxy.dat on the shared disk. The shared disk(s) are mounted relatively late in the startup sequence - hence the authorization files are not available durring DECNET-Plus startup. I do however set the logical NET$IGNORE_DECNET to TRUE and that disables the startup of decnet. The problem now being that I somehow am not able to start DECNET-Plus at a later time. Any clue to what I might have missed?

[Wim Van den Wyngaert]

You have set the logical but you need to define it as false before doing the 2nd startup.

We have no problems with it.

Wim

[Robert Gezelter]

Allan,

Also remember that DECnet resets the MAC Address to a MAC address in the DEC reserved range.

If you have other products that are using the ethernet adapter, this can cause a problem.

You can also move the mounting of the shared disk to an earlier point in the startup. I commented on this in my DECUS presentation "SYSMAN for Improved Restart Performance" (slides are available through my www site at http://www.rlgsc.com/decus/usf99/index.html ).

- Bob Gezelter, http://www.rlgsc.com

[Michael D. Feeney]

Allan, What error messages are you getting when you try to start DECnet? Did you move the NET$PROXY.DAT file to the shared disk too?

I have a similar set up to yours. I moved the same files to a common device, but I mount that device early in SYLOGICALS.COM. I haven't had a problem with DECnet starting.

Could the problem be having separate system disks, but trying to share some of the same files?

[Wim Van den Wyngaert]

What Robert says is start decnet before any other network protocol (lat, ip). Or you are in trouble.

Wim

[John Gillings]

Allan,

>The shared disk(s) are mounted relatively
>late in the startup sequence - hence the
>authorization files are not available
>durring DECNET-Plus startup.

That's the real problem here. Why not avoid the issue altogether by mounting the cluster common disk earlier?

I recommend your SYLOGICALS.COM procedure mounts the disk, then executes a "DEFINE_CLUSTER.COM" in a known location on that disk. That way all nodes execute the same definitions. One place to edit, guaranteed agreement across the cluster, all the necessary logical names are defined, and all the files present when they're required.

Also note there are many more files that either MUST or should be shared across cluster members. See the latest SYLOGICALS.TEMPLATE for the most up to date list.

[John Gillings]

Re: Bob's comment:

>I commented on this in my DECUS
>presentation "SYSMAN for Improved Restart
>Performance"

I too advocate the use of SYSMAN for significantly easier to manage cluster startups. Forget trying to write a "threaded" SYSTARTUP_VMS.COM, use SYSMAN START ADD to define and sequence all your startup procedures. It's then MUCH easier to enable or disable particular products either across the cluster or on individual nodes.

In a multi system disk environment, there are two things you can do to make SYSMAN even more useful...

1) Add a cluster common disk root to the end of SYS$SYSROOT - this means SYS$STARTUP includes your cluster common disk, so startup procedures can live there and be seen by SYSMAN

2) redefine STARTUP$STARTUP_LAYERED to point to a cluster common version of VMS$LAYERED.DAT

(I also copy the common file back to the local system disk, to keep it in synch with the "master" file:

$ DEFINE/SYSTEM/EXEC -
STARTUP$STARTUP_LAYERED -
CLUSTER_STARTUP:VMS$LAYERED.DAT
$ @CLUSTER_FILES:COPY_MODIFIED_FILE -
CLUSTER_STARTUP:VMS$LAYERED.DAT -
SYS$COMMON:[SYS$STARTUP]
)

Check the code in STARTUP.COM - after executing SYLOGICALS, it checks to see if STARTUP$STARTUP_LAYERED has changed. If it has, the old file is closed, and the new one opened. So, the intention is that SYLOGICALS can change the logical name to point to a non-default location, but I don't think it's actually documented anywhere.

This means you can use SYSMAN very effectively in a multi-system disk environment.

[Ian Miller.]

John, good ideas. I think the SYSMAN STARTUP database is an underused facility. Parhaps you can post a link to your presentation.

Setting up multi system disk clusters is not a well documented area.

Allan, I would be interested to know why the shared disk is not mounted until later as SYLOGICALS is the place to do it. I mount the disk there and SYSTARTUP, SYSHUTDWN then only have one line which runs common procedures.